WO2007006377A1

WO2007006377A1 - Device and method for preparing gas mixtures

Info

Publication number: WO2007006377A1
Application number: PCT/EP2006/005376
Authority: WO
Inventors: Klaus Schmidt
Original assignee: Klaus Schmidt
Priority date: 2005-07-14
Filing date: 2006-06-06
Publication date: 2007-01-18
Also published as: EP1907038A1; JP4996604B2; DE102005032977B3; JP2009501031A; CA2615018A1; EP1907038B1; US20070017516A1

Abstract

The invention relates to the preparation of gas mixtures, especially respiratory gases for patients needing artificial respiration, and to an associated device and method enabling the application of an additional gas fraction, especially xenon, in a gas mixture, for example, a respiratory gas for patients, in an especially simple manner, with the smallest possible consumption loss of xenon. The inventive preparation involves a respirator (1) comprising an intubation tube (2), a gas mixing chamber (3), and a pressure generator (4). A selection element (5) is provided between the intubation tube and the mixing chamber, for selecting the target fraction of the return respiratory gas from the rest of the fractions or vice versa, in addition to a target supply connection (7) that is connected to a target fraction tank (10) by means of a controlled supply regulator (9).

Description

Applicant: Prof. Dr. med. Klaus Schmidt

Our file: 67808 AL / HO / GR

Apparatus and method for the treatment of gas mixtures

I. Field of application

The invention relates to the treatment of gas mixtures, in particular of respiratory gases for ventilated patients.

II. Technical background

The need-based provision of gas mixtures in which a predetermined concentration of the individual components is maintained is technically feasible.

If the entire gas mixture is made available to a consumer not in a closed, but in an open circuit and the target fraction of the gas is thereby partially consumed, but the rest of the target fraction must be reused or at least collected, this will be - already much more complex, especially depending on the quantities to be processed and of which target fraction compared to the other fractions is.

If the target fraction is a noble gas, such as xenon, the handling becomes more expensive. In the medical field, however, it has been found that it is precisely the delivery of xenon into the respiratory circuit of ventilated patients that is conducive to sedation and also to the protection of the brain functions of the patient.

However, the benefit of this knowledge is in practice aggravating that

Xenon in the required amount is relatively expensive at a price per liter of about 15 USD and a need per patient of 6 liters per respiratory minute, and is reluctant due to the cost pressure on the purchase of new ventilators that allow xenon supply.

III. Presentation of the invention

a) Technical task

It is therefore the object according to the invention to provide a device and a method which allows the application of an additional gas fraction, especially of xenon, in the context of a gas mixture, for example a respiratory gas for patients, particularly simply and with the lowest possible losses of consumption allowed on xenon. ^

b) Solution of the task

This object is solved by the features in claims 1, 15 and 16. Advantageous embodiments will be apparent from the dependent claims. By means of a controllable feed regulator for the target fraction for the mixture preparation of the respiratory gas, the fraction of the target fraction, for example xenon, in the respiratory gas can be adjusted as required.

If the rest of the respiratory gas still contained no xenon, because, for example, created from the ambient air with the addition of oxygen, no sensor for determining the previous content of the target fraction is necessary.

However, if the ventilated return gas evoked by the patient is recirculated and reused as a breathing gas, with or without the addition of fresh oxygen, the proportion of the target fraction already contained in the return gas must first be determined by a sensor and the additional addition of this target fraction be taken into account.

Irrespective of this, in the gas path of the respiratory back-gas, ie between the intubation tube and either the open outlet for the respiratory return gas or the return to the gas mixing chamber for the preparation of the new respiratory gas, a selection element is present in order to be able to recycle the target fraction:

This may be an active separation device that separates the target fraction from the remainder of the gas mixture if the return gas is to be released to the atmosphere. This could be a centrifuge, or simply a membrane that allows all other components of the return gas to pass through to the environment, but not the target fraction.

If the respiratory return gas is recirculated and used to make a new respiratory gas, the target fraction still contained in the respiratory return gas may be left there, but the breathing respiratory gas used for the treatment of the respiratory gas may need new, different fractions the target fraction can be added (eg, oxygen) or withdrawn (eg, carbon dioxide). Again, it must be ensured that with this addition or deduction of other fractions, the target fraction is not undesirable with deducted.

This can be done by a passive selector z. Example, take place in the form of a membrane through which other fractions can enter or exit the target fraction in the mixing chamber, but the target fraction can not escape.

In this case, the return of the ventilation return gas for the preparation of new respiratory gas must also be the content of the target fraction in the respiratory return gas or after the preparation of the new respiratory gas, but before an additional supply of new target fraction, be known and for this purpose means of a sensor be measured.

The target supply port is then controlled depending on the result of the sensor, preferably by means of an electrical or electronic control, which is preferably coupled to the control of the rest of the respirator or even integrated into this.

If the target fraction is not actively separated from the rest of the respiratory gas, a target purge port for leading the mixture including the target fraction is located in the portion of the gas path that communicates with and is there for the target fraction and / or feed regulator preferably the sensor for the determination of target fraction arranged.

As a result, a separation of the target fraction from the remaining residual fractions is not necessary, and it is only the necessary additional amount of target fraction in the gas path of the total mixture, for example in a dedicated mixing chamber supplied.

For this purpose, a bypass to the main gas path can be formed by means of the destination supply and destination discharge port, which is used for adding to another target fraction by communicating with the reservoir of the target fraction. If the residual gas mixture is not reprocessed but discharged to the environment (open circuit of the main gas mixture) is on the side facing away from the point of consumption of the Zielzufuhr- and Zielabfuhranschlusses the selection element, for example, the selective membrane that allows all fractions except the target fraction passes.

If the main gas mixture is recycled and recycled, such a selection element may not be necessary, for. For example

- The respiratory gas in the reprocessing no fractions must be removed and the return gas newly added amounts about z. B. valves are supplied, which allow a passage only in the supply direction into the gas circuit inside.

In order to provide a retrofittable additional unit for a conventional gas treatment device, such as a respirator, it is possible especially in circulating breathing gas as well as a closed loop of the target fraction or the gas mixture including the target fraction, sensor, supply regulator and also with the Supply controller associated feed connection for the reservoir of target fraction, optionally including the reservoir itself and a possibly unnecessary pressure generator for the target fraction in a target control unit as a closed assembly to mount as a target adapter in the gas path of the processing unit and, for example, a Bypass line forms.

If a selection unit is necessary, this selection device, for example a selective membrane, is preferably also arranged in the adapter or the destination control unit.

In the case of a Y-shaped gas path, this can be in the branch between the Y site and the consumer, ie the patient, but also in the divided branches for Expiration and inspiration, in which then at least the inspiratory branch the target supply port is arranged.

c) embodiments

Embodiments according to the invention are described in more detail below by way of example. Show it:

1 shows a schematic representation of the procedure,

Fig. 2: several general ways to solve the problem and

Fig. 3: concrete designs according to the invention.

FIG. 1 shows in principle how a gas mixture is generated in a mixing chamber 3 from a plurality of basic components A, B, C and conveyed via a line, in this case an intubation tube 2, to a consumer, e.g. B. the patient, is supplied. For this purpose, a pressure generator 4, for example a blower, integrated in the line. This line is to be additionally fed via a destination supply port 7, a further target component Z, which is carried out from a reservoir 10), which takes place with the supply port 7 via a controllable feed regulator 9.

In this case, the gas mixture is not only supplied to the consumer via the line 2, but also the unused remainder, ie the respiratory return gas, is delivered back to the mixing chamber 3 via the line 2.

So that in this case the target fraction Z contained in the ventilation return gas is not lost to the mixing chamber 3 and from there via the component feeders to the outside, a selection element 5 is necessary in the course of the gas path.

This can be an active separation device for separating the component Z from the gas mixture, as a result of which the target component Z is returned to the reservoir. -

7

leads or otherwise can be recycled. This can also be merely a passive barrier that avoids flowing back the target component into the component flows A, B, C.

As indicated in FIG. 2, for this purpose, preferably directly into the mixing chamber 3, the target component Z can be supplied from the reservoir 10 to the mixture, preferably again by pressure build-up by a pressure generator 4 'between the reservoir 10 and the supply port 7.

The content of target fraction in the gas mixture can either in the mixing chamber 3 or in the supply line, z. B. are measured to the intubation tube 2 to the mixing chamber or in the over a target discharge port 8, the total mixture is removed and fed back to the supply port 7 to the supply port 7 to supplement by additional target component Z from the reservoir 10, wherein before the Feeding in the bypass by means of a sensor 6, the content of target fraction Z is measured.

Also open into the mixing chamber 3 are the supply connections for the further components A, B, C, which sometimes have to be additionally added to the respiration gas for preparation. A discharge of the target fraction Z through these supply ports A, B, C is avoided by either lying behind a diaphragm 12 which is not continuous for the component Z, or in which the supply ports for the components A, B, C are formed are that they can be flowed through only in the feed direction into the gas mixing chamber 3, regardless of which fraction.

Fig. 2b, in contrast, shows a solution in which the mixing chamber has a membrane 12, which is permeable only to the target fraction Z and is impermeable to the other components A, B, C.

Accordingly, the target supply port 7, which communicates with the target feed port 13 and in particular a reservoir 10 for this purpose, is located on animal from the outlet, so the intubation tube 2 opposite Side of the diaphragm 12 'in the mixing chamber, while the connections A, B, C for the other components are located on the same side of the membrane as the outlet port.

Fig. 2c shows a solution in which the inspiration path 17 and Expirationspfad 18 with the corresponding hoses from the Y-piece 16 run separately, preferably with a flap for selectively releasing one of the two hoses to the central piece out, the intubation hose.

In the example of FIG. 2c, the expiration tube 18 separates the target fraction Z by means of a membrane 12 ', while the remainder of the respiration return gas is released either to the environment, but then via one for the Z fraction non-permeable membrane 12, or recycled in a circle and supplied to the gas mixing chamber 3 for the treatment of new respiratory gas, in which case the membrane 12 is not required.

The target fraction Z is additionally fed from a reservoir 10 into the mixing chamber for the new respiratory gas via a controllable supply regulator 9, for which purpose a pressure generator 4 'in this supply line may be required.

The target fraction Z withdrawn from the expiration path 17 can also be fed into the reservoir 10, in which case preferably its cleaning device 21 is arranged in this return path.

In this case, therefore, the respiratory gas or respiratory return gas is optionally performed in an open or closed circuit, and also the separated target fraction Z optionally performed in a closed loop or fed to an open recycling despite recycling.

FIG. 3 shows a concrete application of an applicator unit 20, as in a conventional ventilator 1, which supplies the patient via a Y-respirator. Piece 16 and an intubation tube 2 ventilated, can be used later.

In this case, it is assumed that a closed circuit of the respiratory gas or the respiratory return gas is added to the regeneration of the respiratory gas from the return gas in addition to oxygen via a controlled feed regulator 9 and - which is not shown here - optionally CO _{2 is} withdrawn.

According to FIG. 3 a, the applicator unit 20 is arranged between the intubation tube 2 and the Y-piece 16. The applicator unit 20 in this case comprises a target adapter 15, which is mounted as an intermediate piece between intubation tube 2 and Y-piece 16 and from which a bypass 11 branches off analogously to the schematic diagram of Fig. 2a, ie with a sensor 6 for determining the content to target fraction in the gas mixture, a supply of target fraction via a regulated feed regulator 9 from a reservoir 10 of the target fraction and, if necessary, by means of pressure build-up by a pressure generator 4 'arranged in the bypass line.

The supply controller 9 is controlled by a controller 19, which receives the signals of the sensor 6 and is preferably in communication with the controller 19 'of the ventilator 1 or even integrated into it.

The membrane 12 drawn between the feed and discharge ports 7 and 8 for the target fraction Z and the Y-piece 16, which is permeable to all fractions except the target fraction Z, prevents inflow of the target fraction Z into the remaining circuit of the respiratory gas. This is only necessary if the other inlets and outlets of this circuit have an outflow of

Component would allow the circulation. If this is done by special inlet valves for z. B. the oxygen is excluded, can on the membrane

12 are also waived. Fig. 3b shows a solution in which the target supply port 7 and the target discharge port 8 are arranged for the target component Z on the patient side away from the Y-piece 16, in the Expirationsleitung 18 of the target discharge port 8 and in the Inspirationsleitung 17 of the target supply port 7 when the target fraction Z is performed together with the rest here in the bypass 11 in a closed circuit.

Even then, in each case a membrane 12 or 12 'necessary if the rest of the circuit of the respiratory gas, z. As the feed for the oxygen, not by design, a drainage of the target fraction prevented. However, if this is the case, the membranes 12, 12 'can also be dispensed with here.

However, under certain circumstances, the target discharge port 8 can then also be completely dispensed with, provided that the sensor 6 is instead arranged directly in the circulation of the respiratory gas, preferably directly in front of the target supply port 7.

The target supply port 7 then communicates only with the reservoir 10 via the controllable supply regulator 9.

LIST OF REFERENCE NUMBERS

1 ventilator

2 intubation tube

3 gas mixing chamber

4, 4 "pressure generator

5 selection element

6 sensor

7 destination feeder connection

8 destination discharge connection

9 Feed regulator

10 reservoir

11 bypass

11a, b bypass lines

12, 12 'membrane

13 target supply connection

14 target control unit

15 target adapters

16 Y-pieces

17 inspiratory tube

18 expiratory hose

19 control

20 applicator unit

21 cleaning device

Claims

-12PATENTANSPRÜCHE

1. ventilator (1) with an intubation tube (2), a gas mixing chamber (3) and a pressure generator (4), characterized in that - between the intubation tube (2) and mixing chamber (3) a selection element (5) with respect to the target fraction (Z) of the breathing return gas from its residual fractions (remainder) or vice versa, and a target feed port (7) communicating with a controlled feed regulator (9) with a target fraction reservoir (10).

2. ventilator (1) according to claim 1, characterized in that

- At least one sensor (6) for determining the concentration of the target fraction (Z) in the gas path of the respiratory gas of the ventilator is present and

- The sensor (6) controls the feed regulator (9)

3. ventilator (1) according to any one of the preceding claims, characterized in that the selection element (5) is an active separation device for separating the target fraction (Z) from the remaining fractions (remainder) of the ventilation return gas.

4. ventilator (1) according to any one of the preceding claims, characterized in that the selection element (5) is a passively acting selective barrier, in particular a membrane, which is responsible for the target fraction on the one hand and the remaining fractions on the other hand, optionally in dependence on a passage direction, a different permeability.

5. ventilator (1) according to any one of the preceding claims, characterized in that with the target supply port (7), a pressure generator (4 ') is in communication.

(closed loop)

6. ventilator (1) according to any one of the preceding claims, characterized in that a target-discharge port (8) in the part of the gas path of the respiratory gas is present, which with the reservoir (10) and / or the supply regulator ( 9) and in particular contains the sensor (6), whereby a bypass (11) communicating with the reservoir (10), in particular for the total mixture, is formed.

7. ventilator (1) according to any one of the preceding claims, characterized in that the selective membrane (12), in particular in both directions, only for the target fraction (Z) is permeable, but not for the other fractions of the gas mixture, and the target discharge port (8) is located on the target fraction clean side of the membrane (12).

(planned solution)

8. ventilator (1) according to any one of the preceding claims, characterized in that the membrane (12) for all other fractions except the target fraction (Z) of the gas mixture is permeable, and this property applies in particular for both flow directions of the membrane, and Feed port (7) and discharge port (8) on the target mixture side of the membrane (12) open. W ^

9. ventilator (1) according to any one of the preceding claims, characterized in that

Sensor (6), controller (9) and at least the destination feed port (13) for the reservoir (10), in particular including the reservoir (10), possibly also a target pressure generator (4 '), in a target Control unit (14) are housed as a closed assembly, which is connectable via the bypass lines (11a, b) with the ventilator (1). ^"

10. ventilator (1) according to any one of the preceding claims, characterized in that the ventilator (1) in the gas path comprises a target adapter (15) for connecting the target control unit (14), the selection element (5), in particular the Membrane (12), and can be used as an intermediate piece between the intubation tube (2) and gas mixing chamber (3), in a Y-shaped path, in particular downstream of the Y-piece (16) in the intubation tube (2).

11. The ventilator (1) according to any one of the preceding claims, characterized in that the target adapter (15) together with the bypass lines (11a, b) and the target control unit (14) a uniform, in particular retrofittable, applicator Form unit (20).

12. The ventilator (1) according to any one of the preceding claims, characterized in that the supply controller (9) and possibly the sensor (6) with a particular electrical or electronic control (19) is coupled, which are jointly capable of to maintain a constant concentration of the target fraction (Z) in the mixture of the respiratory gas.

13. ventilator (1) according to any one of the preceding claims, characterized in that the target fraction (Z) is a noble gas, in particular xenon. -

15

14. The ventilator (1) according to any one of the preceding claims, characterized in that the control (19) for the target fraction (Z) with the controller (19 ') of the ventilator (1) coupled, in particular integrated in this is.

15. A method for reuse and admixture of a target gas fraction in a gas mixture, characterized in that the gas mixture is circulated over the consumer, which at least partially consumes the target gas fraction, the concentration of the target fraction in the mixture at least one point of the cycle is measured, in particular constantly measured, and the supply of additional target fraction is controlled by comparing the target concentration with the actual concentration.

16. The method according to claim 15, characterized in that the measurement of the actual concentration of the target gas fraction takes place immediately after the consumer.

17. The method according to any one of the preceding method claims, characterized in that the measurement of the actual concentration of the target gas fraction in a bypass for taking out the mixture and supplying the mixture with the added target fraction from the main circuit takes place.

18. A method for reuse and admixture of a target gas fraction in a gas mixture, characterized in that the gas mixture is conducted in an open circuit and the target gas fraction before the outlet of the open circuit separated from the rest of the mixture and the target gas Reservoir is supplied in particular for the target gas supply with time offset, in particular due to reprocessing and compression.